...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Biochemistry >Implications of Surface Charge and Curvature for the Binding Orientation of Thermomyces lanuginosus Lipase on Negatively Charged or Zwitterionic Phospholipid Vesicles As Studied by ESR Spectroscopy
【24h】

Implications of Surface Charge and Curvature for the Binding Orientation of Thermomyces lanuginosus Lipase on Negatively Charged or Zwitterionic Phospholipid Vesicles As Studied by ESR Spectroscopy

机译：ESR光谱法研究表面电荷和曲率对嗜热单胞菌脂肪酶在带负电或两性离子的磷脂囊泡上的结合方向的影响。

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The triglyceride lipase (EC 3.1.1.3) Thermomyces lanuginosus lipase (TLL) binds with high affinity to unilamellar phospholipid vesicles that serve as a diluent interface for both lipase and substrate,but it displays interfacial activation on only small and negatively charged such vesicles [Cajal,Y.,et al.(2000) Biochemistry 39,413-423].The productive-mode binding orientation of TLL at the lipid-water interface of small unilamellar vesicles (SUV) consisting of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphati-dylglycerol (POPG) was previously determined using electron spin resonance (ESR) spectroscopy in combination with site-directed spin-labeling [Hedin,E.M.K.,et al.(2002) Biochemistry 41,14185- 14196].In our investigation,we have studied the interfacial orientation of TLL when bound to large unilamellar vesicles (LUV) consisting of POPG,and bound to SUV consisting of 1 -palmitoyl-2-oleoyl-sn-glycero-3-phosphatidylcholine (POPC).Eleven single-cysteine TLL mutants were spin-labeled as previously described,and studied upon membrane binding using the water soluble spin-relaxation agent chromium(III) oxalate (Crox).Furthermore,dansyl-labeled vesicles revealed the intermolecular fluorescence quenching efficiency between each spin-label positioned on TLL,and the lipid membrane.ESR exposure and fluorescence quenching data show that TLL associates closer to the negatively charged PG surface than the zwitterionic PC surface,and binds to both POPG LUV and POPC SUV predominantly through the concave backside of TLL opposite the active site,as revealed by the contact residues K74C-SL,R209C-SL,and T192C-SL.This orientation is significantly different compared to that on the POPG SUV,and might explain the differences in activation of the lipase.Evidently,both the charge and accessibility (curvature) of the vesicle surface determine the TLL orientation at the phospholipid interface.
机译：甘油三酸酯脂酶（EC 3.1.1.3）嗜热单胞菌脂酶（TLL）与单层磷脂囊泡具有高亲和力，单层磷脂囊泡既是脂肪酶和底物的稀释剂界面，但仅在小且带负电荷的此类囊泡上显示界面活化作用[Cajal ，Y.，et al。（2000）Biochemistry 39,413-423] .TLL在由1-棕榈酰基-2-油酰基-sn-甘油组成的小单层囊泡（SUV）的脂质-水界面上的生产方式结合取向以前使用电子自旋共振（ESR）光谱结合定点自旋标记确定了-3-磷脂酰甘油（POPG）[Hedin，EMK，et al。（2002）Biochemistry 41,14185-14196]。研究中，我们研究了TLL结合到由POPG组成的大单层囊泡（LUV），并结合到由1-棕榈酰基-2-油酰基-sn-甘油-3-磷脂酰胆碱（POPC）组成的SUV时的界面取向。 -半胱氨酸TLL突变体被自旋标记为previo使用水溶性自旋松弛剂草酸铬（III）（Crox）进行膜结合研究。此外，丹磺酰标记的囊泡还显示了TLL上每个自旋标记与脂质膜之间的分子间荧光猝灭效率。 ESR暴露和荧光猝灭数据表明，TLL比两性离子PC表面更靠近带负电的PG表面，并且主要通过与活性部位相对的TLL凹面背面结合POPG LUV和POPC SUV。残基K74C-SL，R209C-SL和T192C-SL。这种取向与POPG SUV上的显着不同，这可能解释了脂肪酶活化的差异。很明显，其脂肪和可及性（曲率）囊泡表面决定了磷脂界面上的TLL方向。

著录项

相似文献

  • 外文文献
  • 中文文献
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号